confusing the revenue from sales of adult books with the revenue from sales of children’s and YA books.

treating all ISBNs issued in a year as a measure of new titles published, regardless of whether those codes were used on reprints or other editions rather than new titles, or not used at all.

combining novels published for teens with all other “Juvenile” titles, including picture books, novels for younger kids, nonfiction, and possibly even educational and library titles.

Roger Sutton at The Horn Bookadded some remarks, evidently based on the number of titles his magazine tracks.

The errors were spread out among the Atlantic article’s sources. That magazine’s writer was far from alone in struggling to find reliable statistics about trade book publishing because the industry does such a lousy job at tracking itself. Simply put, no one has any idea how many new children’s books are published in America each year, or how to consistently separate educational and library books from trade books, children’s from YA, new books from reprints.

Anyone who’s been watching American book publishing knows that there’s been a boom in YA titles, and that that category is one of the few bright spots of growth of recent years. But as for providing a handy, meaningful statistic reflecting that trend which will look good in a news article? Not a chance.

Over in the comics world, Vaneta Rogers at Newsarama examined the basis for a widely quoted complaint from one fan at the San Diego Comic-Con about the percentage of female creators at DC Comics dropping from 12% to 1% with its fall reboot:

The 12 percent number stems from a "gendercrunching" article by blogger Tim Hanley that was calculated from May's comics using all DC titles, including DCU, Vertigo, Johnny DC, video game tie-in comics and more. It counts editors, assistant editors, colorists, inkers and letterers along with writers, pencilers and cover artists.

In fact, if you look at Hanley's numbers, a large proportion of that percentage of females at DC are editors.

On the other hand, the 1 percent number from the same blogger does not include Vertigo or any other publication outside the 52 new DCU titles. The statistic counts only artists, writers and covers. No colorists. No letterers.

And no editors.

Newsarama did an apples-to-apples comparison of the writers, pencillers, inkers, and cover artists alone, and found that there was no statistically significant change. That’s because so few women filled those roles in both sampled months—five or fewer, and less than 10% of all contributors. The reboot that’s attracted fans’ attention and occasional ire doesn’t affect the long-term gender imbalance in superhero-comics publishing at all.